1. Field of the Invention
The present invention relates to a liquid crystal display of a simple matrix type or an active matrix type and more particularly to a liquid crystal display suitable for high-quality display by optimizing the geometry of transparent electrodes formed on the liquid crystal display element substrate.
2. Description of the Prior Art
The liquid crystal display comprises, for example, a liquid crystal display unit (hereinafter simply referred to as an LCD), a backlight disposed under the liquid crystal display unit to supply light to the liquid crystal display unit, a drive circuit for the liquid crystal display unit arranged outside the outer periphery of the liquid crystal display unit, a molded frame body holding these members, and a metal frame which accommodates these members and has a liquid crystal display window. The liquid crystal display unit includes two insulating substrates made of transparent glasses (called electrode substrates) which are placed as to be opposite to each other with a predetermined distance in between in such a way that the surfaces of the insulating substrates on which transparent pixel electrodes for display and a molecular alignment layer are so stacked as to face each other; a sealing material provided between the insulating substrates and along the circumferential portion of the insulating substrates for joining these insulating substrates together; liquid crystal fed and sealed inside the sealing member between the insulating substrates through a liquid crystal injection port provided at one part of the sealing member; and polarizing plates provided outside the insulating substrates.
The liquid crystal display unit and the drive circuit board are electrically connected by a tap carrier package (TCP) where a semiconductor integrated circuit chip for driving the liquid crystal display unit is mounted.
More specifically, a large number of output terminals of the circuit board and a large number of input terminals (outer leads on the input side) of the TCP are connected by soldering. A large number of output terminals (outer leads on the output side) of the TCP and a large number of input terminals of the liquid crystal display unit connected to the display electrodes (the input terminals are formed and arranged at the end portion of the surface of one of the transparent glass substrates or electrode substrates constituting the liquid crystal display unit) are connected by an anisotropic conductive film. A large number of input terminals of the semiconductor integrated circuit chip mounted on the TCP are connected to a large number of inner leads on the output side of the TCP, and a large number of output terminals of the semiconductor integrated circuit chip are connected to a large number of inner leads on the input side of the TCP.
In a simple matrix liquid crystal display unit, transparent electrodes are parallely formed on the facing surfaces of the two substrates, respectively. When viewed from a direction perpendicular to both substrates surfaces, the parallel transparent electrodes on the two substrates cross (actually, they do not cross), and intersections form pixels, i.e., effective display areas.
Among literatures describing such a liquid crystal display are Japanese Patent Laid-Open No. 214548/1986 and Japanese Utility Model Laid-Open No. 13765/1990.
FIGS. 29A and 29B are schematic plan views showing conventional transparent electrode wiring on the upper and lower electrode substrates.
Of the two electrode substrates constituting a liquid crystal display unit, the lower electrode substrate (also called a data electrode substrate or segment electrode substrate) 312 has on its surface parallel lower electrodes (also called data drive element electrodes or segment electrodes) 332, and the upper electrode substrate (also called a scanning electrode substrate or common electrode substrate) 311 has on its surface parallel upper electrodes (also called scanning drive element electrodes or common electrodes) 331.
These two upper and lower electrode substrates 311, 312 are superposed and assembled into a simple matrix liquid crystal display unit (see FIG. 20). The parallel upper electrodes 331 and parallel lower electrodes 332 formed on the facing surfaces of the two substrates are arranged perpendicularly to each other (they cross without contacting each other) when the completed liquid crystal display unit is seen in a direction perpendicular to the surfaces of these substrates. Each cross point constitutes one pixel, that is, each cross point region forms an effective display region.